ci: disable freebsd-12 task

.cirrus.yml

@@ -1,14 +1,15 @@
 task:
-  name: freebsd-12-amd64
-  freebsd_instance:
-    image_family: freebsd-12-4
-  setup_script:
-    - pkg update
-    - pkg install -y pkgconf git sdl2 python fontconfig opus
-    - git submodule update --init --recursive
-  test_script:
-    - ./scripts/cirrus/build_freebsd.sh dedicated
-    - ./scripts/cirrus/build_freebsd.sh full
+# Seems packages for it were removed from the mirrors
+#  name: freebsd-12-amd64
+#  freebsd_instance:
+#    image_family: freebsd-12-4
+#  setup_script:
+#    - pkg update
+#    - pkg install -y pkgconf git sdl2 python fontconfig opus
+#    - git submodule update --init --recursive
+#  test_script:
+#    - ./scripts/cirrus/build_freebsd.sh dedicated
+#    - ./scripts/cirrus/build_freebsd.sh full
 
 task:
   name: freebsd-13-amd64